The present invention relates to electrical connectors, and more particularly to electrical connectors for terminating flat conductor cables.
Flat conductor cable was developed as an alternative to present electrical installation practice utilizing troughs/conduit placed below floor level. The flat cables are intended to be placed flush to the floor surface with the necessary branch circuits leading to the desired locations with carpeting then placed over the cable to provide a surface suitable for interior use and for personnel traffic. With such a system, it is necessary to provide electrical receptacles in the housing for termination at each of the desired locations. Coupled with this requirement is the requirement for suitable electrical/mechanical termination of the flat conductor cable, which is generally of a thin rectangular cross-section.
Prior art techniques for terminating flat cable conductors, especially those for use with telecommunications equipment, have included complicated, specialized termination connectors for a plurality of conductors of flat cable which are then adapted to mate with other suitably designed connectors which are connected, for example, to a plurality of round wire conductors to provide for transition from the flat cable conductors to the rounded wire conductors. For example, such an arrangement may be seen in U.S. Pat. No. 3,760,335 which shows a housing for receiving the flat cable in one side and which are adapted to mate with a complimentary connector on the other side.
Another prior art technique for terminating flat conductor cables has included insulation piercing techniques for providing a rounded opening for mounting purposes. An example of such a prior art technique is shown in U.S. Pat. No. 3,549,786. In one embodiment of this patent, rounded openings for mounting are provided in both the upper and lower surfaces of the connector which are intended to accept a mechanical type fastener (such as for example a screw) utilized for mounting of the assembled connector to an appropriate termination device or mounting surface. After mounting of the connector on the flat cable conductor, a corresponding opening must be cut, punched, or drilled through the conductor to accept the mechanical fastening means. It should be noted that after insulation, both the upper and lower halves of the connector must be in proper alignment to provide an opening which is interference free to allow for the mechanical fastener to have free access through the connector for attachment to an appropriate termination device.
As can be appreciated, this procedure requires additional installation techniques with associated added tooling expenditures as a result thereof. Further, it should be appreciated that difficulties may also be experienced in maintaining proper alignment of the upper and lower connector halves during assembly of the connector onto the flat conductor. Further still, high concentration forces directly under the mechanical fastener may be transferred to the connector faces during the tightening process which, because of a lack of support directly under the fastener, may cause bending or dishing of the connector surface during tighening. That is, the contact surface acts as a simply supported beam having the ends or outer edges supported by the insulation piercing mechanism with the mechanical fasteners then exerting a concentrated load causing bending or lowering of the contact surface at the center. This action may tend to relieve pressure in the insulation piercing mechanism thereby reducing the electrical contact effectiveness.